from django.db import models
# 如下为新增代码
from django.utils import timezone
from django.contrib.auth.models import User
from django.db.models.query	import	QuerySet
from django.urls import reverse
from taggit.managers import TaggableManager

class PublishedManager(models.Manager):
    def get_queryset(self) -> QuerySet: 
        return super(PublishedManager,self).get_queryset().filter(status='published')

class Post(models.Model):
    objects = models.Manager()
 # 使用自定义模型管理器PublishedManager类创建一个管理器实例
    published = PublishedManager()
    STATUS_CHOICES = (
    ('draft', 'Draft'),
    ('published', 'Published')
 )
    tags = TaggableManager()
    title = models.CharField(max_length=250)
    body = models.TextField()
    slug = models.SlugField(max_length=250, unique_for_date='publish')
    author = models.ForeignKey(User, on_delete=models.CASCADE,related_name='author')
    publish = models.DateTimeField(default=timezone.now)
    created = models.DateTimeField(auto_now_add=True)
    updated = models.DateTimeField(auto_now=True)
    status = models.CharField(max_length=10, choices=STATUS_CHOICES,default='draft')
    class Meta:
        ordering = ('-publish',)
    def __str__(self):
        return self.title
    def get_absolute_url(self):
        return reverse('blog:post_detail', args=[self.publish.year,
        self.publish.month, self.publish.day, self.slug])   

class Comment(models.Model):
    post = models.ForeignKey(Post,
    on_delete=models.CASCADE,
    related_name='comments')
    name = models.CharField(max_length=80)
    email = models.EmailField()
    body = models.TextField()
    created = models.DateTimeField(auto_now_add=True)
    updated = models.DateTimeField(auto_now=True)
    active = models.BooleanField(default=True)
    class Meta:
        ordering = ('created',)
    def __str__(self):
        return f'Comment by {self.name} on {self.post}'

